The present invention relates to fastening arrangements for automotive lighting fixtures and more particularly, to a means of fastening a metal array of light emitting diodes to a plastic support in a light fixture.
Light emitting diodes are becoming more common in automotive lighting fixtures because of the amount of luminosity for their compact size, and the flexibility of their configuration in lighting arrangements. Additionally, light emitting diodes permit more artistic and aesthetically pleasing light arrays which give the automotive lighting fixture a more desirable or unique appearance.
Light emitting diodes or LEDs are special diodes that emit light when connected in an electrical circuit. The LED contains a semi-conductor chip which has two separate regions separated by a junction and when sufficient voltage is applied to the chip across the leads of the LED, current flows through the diode and light in a very narrow frequency range is emitted. The color of the light emitted can be affected by the different semi-conductor materials utilized in the LED. LEDs have certain advantages over incandescent bulbs in that they do not have a filament which will bum out and the light emitting portion does not get particularly hot, although the base portion does. They are illuminated solely by the movement of electrons in the semi-conductor material and they will last as long as a standard transistor. Thus, it is not uncommon for LEDs to have over 100,000 hours of continuous life. Consequently, LEDs are very desirable for automotive lighting fixtures where long bulb life is a desirable attribute.
One disadvantage of LEDs is that individually, they do not emit sufficient light for automotive purposes. Accordingly, it is necessary to have a number of LEDs or an array of LEDs which in combination emit sufficient light for automotive lighting purposes. However, problems have been experienced in attaching an LED array in an automotive lighting fixture. Typically, the LED array is arranged on a metallic circuit board and that metallic circuit board must be attached to the plastic of the light fixture in a manner which will assure that it remains in position and does not vibrate loose as a result of the vibration of an automobile. Accordingly, in the past, such LED arrays have been attached by screws or metal fasteners or in some instances by sonic welding. However, such prior art techniques require additional parts and labor which increase the cost of the LED lighting fixture. Accordingly, it would be a desirable advance in the art to provide a means of securely attaching LED arrays in automotive lighting fixtures which does not involve time consuming labor steps or additional parts. Accordingly, it would be an advance in the art to provide a means of securely attaching an LED array into a lighting fixture that requires no special tools and can be accomplished quickly without time consuming labor steps.
A mounting assembly for at least one array of light emitting diodes (LEDs) comprises at least one metal circuit board and mounting bracket. The circuit board have one or more LEDs attached thereto and at least one first engaging opening and at least one second engaging opening formed through the circuit board. The first engaging opening has a larger portion and an elongated narrowed portion with engaging surfaces adjacent opposite edges of the narrowed portion. A mounting bracket is formed of a electrically non-conducting material. The mounting bracket has at least one mounting surface for receiving and supporting the circuit board. The mounting bracket has formed on the mounting surface at least one first engaging tab and at least one second engaging tab. The first engaging tab has a narrow portion extending outwardly to an outward end from the surface and a larger portion connected to the outward end of the narrow portion so that there is a gap formed between the edges of the larger portion and the mounting surface. The larger portion is dimensioned to be able to be passed through the larger portion of the first engaging opening but too large to pass through the elongated narrowed portion of the first engaging opening. The narrow portion of the first tab being dimensioned to be able to fit into the elongated narrowed portion of the first engaging opening so that the larger portion of the first tab engages the engaging surfaces when the narrow portion of the first tab is moved into the elongated narrowed portion of the first engaging opening. The second engaging tab is configured and positioned to enter and engage the second engaging opening when the narrow portion of the first tab is moved into the elongated narrowed portion of the first engaging opening to retain the circuit board in position against the mounting surface.
The larger portion of the first tab may be essentially square in shape, and the narrow portion may be essentially rectangular in shape with the rectangular dimensions less than the square dimensions of the larger portion. Also, the larger portion of the first engaging opening may be essentially square in shape and dimensioned to allow the square shaped larger portion of the first tab to pass through the square shaped larger portion opening. The elongated narrowed portion of the first opening may be essentially rectangular in shape and dimensioned to receive the rectangular shaped portion of the first tab.
Also, the second engaging tab may be essentially cylindrical in shape with a tapered upper surface upwardly tapered away from the first engaging tab. The second engaging opening may be circular in shape and positioned and dimensioned to receive the second engaging tab when the first narrow portion of the first tab is moved into the elongated narrowed portion of the first engaging opening.
Thus, the present invention provides a quick effective way of attaching a metal circuit board to a non-conductive mounting bracket that does not require special tools or fasteners.